Data Coupling is defined as “the manner or degree by which one software component influences the execution of another software component" in the
Clarification of Structural Coverage Analyzes of Data Coupling and Control Coupling document edited by the
Certification Authorities Software Team (CAST). The purpose is 'to provide a measurement and assurance of the correctness of these modules/components’ interactions and dependencies'. Data Coupling is used to verify that all the global variables of the application under test have been consumed in read (also called
use) and write (also called
def) during the tests.